A large number of injections of various liquids into the human body with a syringe having a needle thereon occurs each day in numerous locations including doctors' offices, hospitals, mobile intensive care units and the like. It is well known that in the process of giving an injection, the person giving the injection may accidentally come in contact with the exposed needle tip. This problem is of great significance today in view of the AIDS epidemic. It is important that a protector be provided that prevents accidental exposure to the needle. Such protection must be simple and easy to use and inexpensive to manufacture because of the large number that must be provided.
The present invention relates to a device to protect against accidental exposure to the needle on a hypodermic syringe. A flexible tubular covering made of silicone or other elastomeric material is attached to the syringe surrounding the needle and extends beyonds the tip of the needle. A cap is mounted on the end of the tubular covering to enclose the needle tip. An orifice extends through the cap such that as the cap is retracted toward the syringe, the tubular covering is flexed allowing the needle to pass through the orifice in the cap. In the preferred embodiment, at least two-spaced slits extend down the tubing from a point below the cap mounting to a point above the syringe attachment such that when the cap is pushed toward the syringe, the slit tube compresses outwardly on each side of the needle allowing the needle to pass through the cap orifice. The compressed tube acts as a spring and returns the cap over the needle tip after use of the needle. The cap is cylindrical in shape with a reduced diameter base for attachment of the elastomeric tubing and is open at only the end of the cap forming the reduced diameter base. The orifice is in the other closed end and in one embodiment is placed off center such that the cap must be deliberately pushed to one side to align the orifice with the needle thereby tending to prevent accidental exposure of the needle when the cap is inadvertently moved toward the syringe.
In another embodiment, a horizontal slot is formed in the side of the cap and a plate is slidably mounted in the cap slot for orthogonal movement with respect to the longitudinal axis of the cap. An orifice is positioned at one side of the plate such that the plate orifice is aligned with the cap orifice only when the plate is orthogonally moved with respect to the cap. This action enables the needle to pass through the aligned orifices when the cap is pushed toward the syringe. If desired, a resilient spring may be positioned between the cap and the slidable plate such that plate will be biased to a normal first position to cause the plate orifice to be out of alignment with the cap orifice to prevent accidental exposure of the needle if the cap is inadvertently moved toward the syringe and such that the plate may be forced to a second position aligning the plate orifice and cap orifice for enabling needle exposure and simultaneously compressing the resilient spring so that the plate will be returned to the normal first position when the force is removed.
In one embodiment, the plate is formed of molded plastic and the resilient spring is S-shaped and integrally formed at one end with the molded plastic plate. Further, a projection is integrally molded on the other end of the resilient spring and a recess is provided in the interior of the cap on the side opposite the slot such that the recess receives the projection on the resilient spring to hold the resilient spring in a stable position in alignment with the slot and the cap.
If desired, where the outer end of the syringe around the needle has a first diameter, the flexible tubular covering is utilized that has a second diameter sufficiently smaller than the first diameter such that the flexible covering can be forced over the first diameter of the syringe outer end to frictionally hold the cap in the retracted position during use of the needle and release it after use to return the cap to its normal position covering the needle tip.
If desired, the flexible tubular covering may be in the form of a bellows that, in a normal position, holds the outer end or cap covering the needle tip and, in a second position, when the bellows is compressed, allows the needle to pass through the orifice in the cap and the cap retracted. Again, where the outer end of the syringe around the needle has a first diameter, the bellows has a mating tubular end adjacent the cap with a second diameter sufficiently smaller than the first diameter of the outer end of the syringe such that the mating tubular end can be forced over the diameter of the syringe outer end to frictionally hold the cap in the retracted position during the use of the needle and be released after such use to return the cap to its normal position covering the needle tip.
The cap may have a solid body with a base for attachment to the flexible elastomeric tubing and an orifice extending longitudinally through the solid body of the cap. A molded horizontal slot may be formed in the cap extending at least partially through the solid cap orthogonal to the orifice. A plate is slidably mounted in the cap slot for orthogonal movement between first and second positions and an orifice is formed in the plate out of alignment with the cap orifice in the first plate position such that when the plate is moved to the second position, the plate orifice is in alignment with the cap orifice to enable the needle to pass through the aligned orifices when the cap is forced toward the syringe. The plate may have a resilient annular band eccentrically surrounding and attached to it on one side thereof to form a spring member movable between first and second positions. An elongated flat member serves as the plate and is attached at one end to the inside of the annular band with the other end inserted in the cap slot. The other side of the annular band is attached to the outside of the cap in alignment with the slot. The band, in such configuration, holds the plate in a first position. When the band is squeezed, the plate is forced inwardly in the slot to a second position. An orifice is formed in the flat member such that, in the first position of the band, the flat member orifice and the cap orifice are out of alignment and, in the second position of the band, the flat member orifice is in alignment with the cap orifice to allow the needle to pass therethrough when the cap is forced toward the syringe.
If desired, the resilient annular band may be formed in the shape of an oval that eccentrically surrounds the cap to form a spring member movable between first and second positions. A first elongated flat member serves as the plate and is attached at one end to a first position on the inside of the annular band on the minor axis of the oval and extends into the slot. A semicircular orifice is formed in the outer end thereof. A second elongated flat member is attached at one end to a second position on the inside of the annular band diametrically opposed to the first position on the minor axis of the oval and extends into the slot such that the outer ends of the two elongated members overlap. A second semicircular orifice is formed on the outer end of the second elongated flat member such that, in the normal first position of the oval shaped band, the two flat members overlap each other to prevent the needle tip from entering the cap orifice and when the oval shaped band surrounding the cap is compressed along the major axis, the outer ends of the first and second flat members move away from each other until the semicircles in the two members form a complete circle through which the needle can pass to the cap orifice.
Thus, it is an object of the present invention to provide a device that protects against accidental exposure to the needle on a hypodermic syringe.
It is also an object to the present invention to provide a protective covering surrounding the needle and attached to the syringe with a cap on the outer end thereof beyond and covering the needle tip and having an orifice in the cap such that when the cap is forced toward the syringe, the needle may pass through the orifice in the cap for use.
It is yet another object of the present invention to provide a resilient covering for a hypodermic needle that has a memory such that when the covering is compressed to expose the needle, it is automatically biased to cause it to return to its initial position covering the needle when it is released.
It is still another object of the present invention to provide a covering to protect against accidental exposure to a hypodermic needle, the covering having a cap on the outer end thereof that has an orifice through which the needle can pass. The covering is of such an inside diameter that it can frictionally adhere to the outer portion of the syringe below the needle to hold the cap in its retracted position until use of the needle is completed and then the compressed covering may be forcibly removed from its frictional engagement such that the compressed covering may return the cap to its initial position covering the needle tip.
It is also another object of the present invention to provide a bellows-type covering to protect against accidental exposure to a hypodermic needle, the bellows-type covering having a cap on the outer end thereof that has an orifice through which the needle can pass. The bellows has an outer end of such an inside diameter that it can frictionally adhere to the outer portion of the syringe holding the needle to hold the cap in its retracted position until use of the needle is completed and then the compressed bellows may be forcibly removed from its frictional engagement such that the bellows returns the cap to its initial position covering the needle tip.